1. Field of the Invention
This invention relates to a device and method for inducing the release of antimicrobial agents from a conductive medium. In particular, the present invention comprises a device and method for the sterilization or reduction of a microbial population in or on a medium by the application of intermittent and/or reverse polarity electrodes placed within or on the medium.
2. Description of the Relevant Art
There are many environments in which it becomes necessary to control the growth of bacteria. During food processing or potable water storage, it is important that the amount of microbes or bacteria be substantially reduced if not eliminated. Equally important is the need for maintaining a sterile environment during most, if not all, surgical operations. Not only must the medical devices which permeates a patient's skin be maintained sterile, but the incision area must also be substantially void of bacteria or microbes.
As a means to reduce or prevent the likelihood of infection following an incision, topical antibiotics are often applied at the point of incision around the medical instrument. In addition, antibiotics can be injected into the physiological system to further ward off infection. Unfortunately, many forms of chemical-based antibiotics may cause serious side effects. Furthermore, if an incision or insertion is maintained over a relatively long period of time such as, for example, when a catheter is place through the skin, detrimental effects caused by long-term antibiotic use is substantially increased.
In an effort to overcome the problems associated with conventional antibiotics, iontophoresis was recently introduced as a means for electrically sterilizing the incision or insertion site. The iontophoresis process consists of introducing a low level current into a conducting medium such as fluid contained within a physiological system. A current is supplied to the electrodes which thereby induces ionic flow of ions from one electrode to the other. Specifically, conventional iontophoretic devices utilize heavy metal ion movement between electrode to produce the desired killing effect. Thus, conventional iontophoresis primarily involves the generation of metallic ions at the electrode surface which are then subsequently driven into the surrounding conducting medium or fluid path by the influence of electromotive force.
Although conventional iontophoresis represents a substantial improvement in long term sterilization, the heavy metal ions generated from the electrode surface likely limits the life expectancy of the electrodes. The out-migration of heavy metal ions from the surface may lead to a reduction in the electrode size and integrity.
Therefore, while conventional iontophoresis devices and methods provide a safer and longer period of sterilization than most forms of antibiotics, their period of use is still limited due to the out-migration process. If conventional iontophoresis is used over extremely long periods such as in a food processing or water treatment environment, then frequent replacement of conventional metallic electrodes is necessary, and would be both time consuming and expensive.